The invention relates to a drive unit for a hybrid motor vehicle for coupling an internal combustion engine and/or an electro-dynamic machine to a transmission.
DE 43 23 601 A1 discloses a drive unit for a hybrid motor vehicle which includes an input shaft, a single disc dry clutch, an output shaft and an electric motor-generator. The input shaft is driven by the internal combustion engine. Within the drive unit, the input shaft is connected to the primary side of the clutch. The output shaft extends to the transmission and is connected within the drive unit to the secondary side of the clutch and the motor-generator. When the clutch is closed, a power path is established from the internal combustion engine via the input shaft and the clutch to the output shaft. The state of the clutch is determined by a throw-out plunger, a throw-out bearing and a closing spring effective in axial direction. During operation by the electric motor, the clutch must be de-activated in order to uncouple the internal combustion engine from the motor-generator. To this end, the closing spring must be held in the non-closing position, that is, a corresponding high holding force must be applied via the throw-out plunger and the throw-out bearing. Critical also is the use of single disc and two-disc dry clutches for hybrid vehicles with high-torque internal combustion engines, of for example, more than 1000 Nm. A single disc dry clutch for the transmission of such high torques requires a relatively large space which increases the weight correspondingly.
It is therefore the object of the present invention to provide a drive unit capable of transmitting a high torque while having only moderately large space requirements.